Why was the gta5 militia border patrol killed?

Being cheated. The two claimed to be the militia Border Patrol, and they were responsible for expelling stowaways. Joey, who could speak English, suddenly took out the so-called "Patriot Detector" and said that he had discovered the stowaway, and they needed Trevor to go with him to watch him. After Trevor had done so much for the patrol, he noticed that one of them was very leisurely, and realized that they were lying to him, so he went on a killing spree. GTA5, also known as "Grand Theft Auto V" (English: Grand Theft Auto V) is an open world action adventure game. GTA5 is produced by Rockstar North.